Draft apparatus for boiler-furnaces.



PATENTED FEB. 6, 1906.

A. H. MAZERAUD. DRAFT APPRATQS POR BOILBR PURNACBS.

APPLIUTE FILED JULY 32, 1905.

PATENTBD PEB. 6, 1906.

A. H. MAZERAUD.

DRAFT PPARATUS FUR BOILBR FURNACES.

.APPLIGA'FION :FILED JULY 22.1905.

3 SHEBTSASHBBT 2V wuewtoz @vita/:amo

PATENTED FEB. 6, 1906.

A. H. MAZERAUD. DRAFT APPRATUS PUR BOILER FURNACES.

APPLIGTIGH FILED JULY 23. 1905.

3 HBBTB-SHEET 3.

UNITED STATES PATENT OFFICE.

DRAFT APPARATUS FOR BOILEFl-FURNACES.

Specification of Letters Patent.

Patented Feb. 6, 1906.

Application filed J'uly 22,1905. Serial No. 270.872.

To al whom t m/a-y concern.-

Be it known that I, ALEXANDRE HONOR MAzERAUD, mechanical engineer, a citizen of the Republic of France, residing at 38iis Rue Vivienne, Paris, France, have invented new and useful Improvements in Draft A aratus for BoilerFurnaces, of which the ollowing is a specification.

The present invention relates to means for utilizing waste steam in order to improve the conditions in which the artificial draft is effected in boilers in an extremely economical and practical manner, the draft being indispensable for obtaining on a reduced gratesurface the combustion of the amount of fuel which is necessary to produce the vaporpressure required for running the engine. The application of the new rinciple to locomotives is taken b way o example and is explained in the fol owing specification.

According to the resent invention this improvement of the raft of locomotives is realized by a new utilization of the waste steam in producing a blast beneath the grating by means of this steam independently of the draft usually obtained by sending the Waste steam into the funnel on its leaving the cylinders. For this purpose the waste-pipe is placed in the smoke-box, as is customary at the present time. The Waste-pipe, however, is rovided withan a propriete re ulator, w 'ch may be used fdr utilizing tins steam under normal conditions to obtain the usual draft or for the purpose of utilizing only a part of the steam to cause the gases of the fire-box to move toward the funnel-and of sending the other part into two special injectors arranged for the use of steam at low tension, having their mouth for the steam at the bottom of the column for the waste and being arranged infront of the ash-box of the locomotive, so that the s eed of the latter in creases the velocity of tlie suction or of the entrance of the air into the injectors. The air thus aspirated is forced into nozzles which, as the case may be, are arranged either in front of the ash-box, the tra -door of which is then kept closed while the ocomotive is in motion, or behind the ash-box, the latter being also kept closed on all its other sides. This draft blown in beneath the grate does not only allow of close-burning fuel (and even residues) being burned, which could not be used in the case of a natural draft which produces an insufficient influx of air for their combustion; but owing to the pressure produced in the ash-box no agglomeration of slag occurs on the grate, and the cleaning of the iireplace consequently becomes less laborious. Moreover, apart from the fact that in case of the draft constituted by the inj ectorsbeing damaged the engine can run under the same conditions as at the present time, {as by a simple operation of the valves the waste can be caused to resume its ordinary useful eect.) A special device isprovided to allow of the use of the injectors being continued in runnin live steam taken om the boiler should the column for the exhaust be damaged or any other reason present itself.

In the aceompanyin drawings, Figure 1 is a sectional elevation s owing the apparatus a plied to a locomotive,nozzles being mounted in front of the ash-box. Fig. 2 is a vertical cross-section along 2 2 of Fig. 1. Fig. 3 is a section along 3 3 of Fig. 2. Fig. 4 is a diagram of the whole contrivance. '5 1s an enlarged detail of the three-way distribution for live steam, section along 5 5 of Fi 6. Fig. 6 is a section along 6 6 of Fig. 5. gs. 7 to 13 are explanatory diagrams showing the operation and the working of this distributer. Fig. 14 is a diagram, partly in horizontal section, showing the arrangement of the apparatus having nozzles mounted for receiving the air at the back of the ash-box, as well as the automatic by-pass. Fig. l5 is a vertical section, on a larger scale, of the bypass shown in Fig. 14.

n, Fig. i denotes the whole of the locomotive, (shown merely in its outlines,) e being the furnace, a2 the ate with its movable section a", and a* the as box,lprovided withadoor a5, Figs. 2 and 3, in front.

On leaving the cylinders the exhaust arrives in the usual Way at b, Fig. 1, at the bottom of the exhaust-column t', the column mounted as usual in the smoke-box a", forming a vertical blastipe, the outlet of which is generally situate at the same height as the upper row of the smoke-pipes. This column, in combination with the funnel aj', constitutes an inector in which the flow of the steam produces in a well-known manner a com arative vacuum, which induces the gases om the 'urnace to rush in, and in consequence ofthe vacuum produced in the furthe engine by means of YSe IDO

nace facilitates the passage of air coming from the ash-box across the fuel-bed.

The blast-pipe b carries any suitable regulator, the operating-axis c of which is alone shown in thc drawings and can be operated by the driver at pleasure by means of the rod c and the lever c2. This regulator is designed in such a manner that the exhaust-steam can be used under normal conditions to obtain the usual draft or only a part of the exhaust may be used in the blast-pipe to merely produce a current of gas from the furnace to the funnel, leavin another part of this steam for a purpose to e described hereinafter. On the other hand, at the bottom of the exhaustcolumn b a tube d is joined, having an operating-valve d, which can be operated by the driver by means of the arm d2, rod d3, and lever d* to regulate at pleasure the passage of the exhaust-steain at that point. The tube d preferably opens into a reservoir e to prevent fluctuation. At this reservoir two tubes e and e2 start, which open, respectively, into a suction-injector ff?, s ecially contrived for the use of steam at ow pressure. Of these tubes one is placed on each side and in front of the ash-box a4. In this way while the engine is in motion the velocity of the locomotive increases the velocity of the airsuction reduced at f by the passage of the steam t irough the injectors. The air thus aspirated is then forced into the nozzles g,

which, if possible, may preferably be arranged, as shown in Fig. 1, in front of the ash-box a4, the trap-door a5 of which is ke t closed while the locomotive is in motion. Xs in certain engines, however, nozzles could not easily be mounted in front of the ash-box owing to the movable grates and in s ite of the use of partially-movable grates an other pecial devices, the arrangement shown in ig. 14 may advantageously be adopted in this case. In this arran ement the injectors, such as f', mounted 1n front of the engine, are always contrived in such a manner that they receive at f air at the s eed of the motion of the engine, this spee being lncreased by the s eed resulting from the suction power of tlie injectors, the air being, however, afterward forced into the nozzles g', arranged at the back of the ash-box a, the latter being also kept closed on all its other sides.

It is readily seen that owing to the above arrangements the exhaust-steam can easily be led away on issuin from the cylinders by means of the waste-tu e b in the usual manner or that by a suitable operation of the levers c2 d4, controlling the valves of the regulater mounted at c and d, either all or a part of the steam may be used to assure the working of the injectors f f2, sucking in air from the outside and forcing it into the ash-box. It is thus possible to combine at pleasure in a permanent or momentary way without any supplementary expenditure of steam and to the extent required the draft caused by the exhaust through the funnel and the draft blown in beneath the grate by means of the injectors or to use these drafts inde )endently of one another. ()n the other hand, the conditions under which the injectors are worked may be modiiied by operating the throttle-valve d of the regulator, according to circumstances, allowing for the power of vaporization required, the nature of the fuel, the state of the fire, &c. It will, moreover, be understood that the operating-levers cZ d* instead of being independent might be combined so as to connect the movement of the valves of the regulator with the admission of steam.

In order to continue in case of need the working of the injectors with live steam, should this be necessary or merely advantageous, owing to the exhaust-column being damaged, for instance, or for some other reason, the following device allows of the draft induced and blown in being combined with a blast of live steam either in a permanent or in a momentary manner and in any desired proportion. From the cock L, Fig. l, for the admission of steam in connnunication with the boiler leads a tube h', which is connected, by means of a three-way distributer i, on the one hand, to the stean'i-blower fixed inside the funnel by means of the tube j, on the other hand by means of the tube c to the connecting-pipe fm, which is joined to two other injectors mfm2,wliich are worked with live steam and are also used for aspiratin air at f, forcing the air into the same nozzIes g (or g) as do the in'ectorsf f2 previously described. rIhe distri uter i (shown on a larger scale in Figs. 5 to 13) consists, essentially, of a box provided with three nozzles, which are re spectively joined to the pipes z, j,and k, and which box is xed to the body of the boiler' a. In this box, which is closed by a screwed head i', a disk or valve n is mounted, which is provided with two notches or ports n 12.2, susceptible of cooperating with two ports by means of the bell-mouthed apertures o o2 at the surface of the seat 0, formed in the box z' and against which the valve n works. The a erture o is in communication with the nozz e joined to the pipe j, which leads to the steam-blower, whereas the aperture 02 communicates with the tube r, joined to the livesteam injectors m m2. The valve o can be operated by the driver by means of the rod p and the handle p', which cooperates with a dial and indicator p2, having several sto s corresponding to the various positions of tfie valve.

On bringing the handle p into position I, Fig. 8, a position of complete closure is attained and no live steam passes either to the steam-blower or to the injectors. In position II, Fig. 9, the distributer passes steam IOO IIO

ISO

through the aperture o' to the steam-blower of the funnel alone. In position III, Fig. 1U, the valve 'n uncovers the aperture c2 and feeds the injectors with steam. In position IV, Fig. 11, the apertures o' and c2 are bothuncovered and steam is admitted both to the steamblower and to the injectors. In position V, Fig. 12, the valve closes half the aperture o2, and. owing to the apertures having a flared form the aperture 0 is still completely uncovered, so that steam is fully admitted to the steam-blower, but only half of the possible amount is admitted to the injectors. Again, in position VI, Fig. 13, the aperture c2 being completely uncovered, Whereas 0 is half closed, steam is fully admitted to the injectors and onl f half the amount possible is admitted to t e steam blower. It is easily seen that on bringing the handle p into the intermediate positions corresponding to the stops VII and VIII; Fig. 7, half the possible amount of steam is admitted to the steamblower and half the amount to the injectors. It is, moreover, possible to combine the action of the injectors f m or f2 m2 on each side, so that they can be Worked together witheXhaust-steam or that the injectors m m2 can be Worked with live steam, either While the injectorsffZ continue to Work with exhaust-steam or after the latter injectors have been stopped whether intentionally or in consequence of damage having been done to the exhaust. In this case use could be made of the automatic by-pass. (Indicated in Fig. 14 and shown in section and on a larger scale in Fi 15.) This device consists of a cylinder g, 1n which a piston g moves freely, the piston having a rod g2, which is suitably guided at its far ends by the cylinder-heads g3 g4. This cylinder is provided with three nozzles r 1" r2, which put its interior in communication as follows: one of them with the pipe e or e2 for exhaust-steam, another with the pipe m for live steam, and the third with the injector m or m2. Owing to this arrangement, it is easil, seen that if the communication between t e admission of live steam and the pipe m bein closed or interrupted exhaust-steam be a mitted to the pipe e (or e2) the pressure of the steam exercised on the ri ht face of the piston g will move it from right to deft, (position of Fig. 15,) so that direct communication will be established between eQor ez) and the injector m', (or m2,) the latter being then worked with exhaust-steam, concurrently with the injector (or f2.) If live steam is admitted to the pipe Im, the admission of exhaust-steam at e (or e2) being interrupted or not, the preponderent pressure of this steam on the left face of the piston g', Fig. 15, will move the piston from left to right and direct communication Will thereby be established'betvveen m and the injector m', (or m2,) which Willthen Work with live steam.

It is seen that by the judicious use of the three-way distributor and of the automatic by-pass described above a permanent or a momentary combination may be arrived at at will and in the proportion required of the induced and blast drafts obtained by cX- haust-steam with the blast with live steam and that benefit can be derived from the advantages which the one or the other kind of draft may oifer, according to circumstances. It need hardly be added that in all cases of blast-draft the steam (Whether live steam or exhaust) mixed with air forced into the ashbox beneath the grate will be decomposed by the hi h temperature to which it will be submitte on coming in contact with the fuel and the hydrogen and oxygen set free will further facilitate the combustion. This new principle of combining in a permanent or a momentary manner and in the proportion re uired t c induced and blast drafts above re erred to may be applied in whole or in part to any other kind of boiler, whether stationary or for marine purposes, moreover the motor Huid may also be any kind of gas suitable for facilitating combustion obtained from any suitable source.

What I claim as my invention, to secure by Letters Patent, is

1. In a draft apparatus for boiler-furnaces, the combination of an ash-box, means for delivering a mixture of exhaust-steam, live steam and air therei'nto, a blast-pipe and regulating means therein, said blast-pipe being connected to the means for deliverin said mixture to the ashbox, substantie ly as shown and described.

2. In a draft apparatus for boiler-furnaces, the combination of an ash-box, a blast-pipe leading to the stack, regulating means in said blast-pipe, connecting means from said blastpipe to said ash-box, a valve for regulating the quantity of exhaust-steam assing into the connecting means, means or injecting live steam into said connecting means, an means for introducing air and thus mixing the live steam, exhaust-steam and air, substantially as shown and described.

3. In a draft apparatus for boiler-furnaces, the combination of an ash-box, an injector provided with an air-inlet, a blast-pipe provided With 4`re ulating means, connections between the b ast-pipe and the injector, a steam-blower, a live-steam pipe leading from the boiler to the injector, and a distributor located in the live-steam pipe for controlling the supply of steam to the injector and steamblower, substantially as described.

4. In a draft apparatus for boiler-furnaces, the combination of an ash-box, injectors provided with air-inlets, a blast-pipe, means for regulating the exhaust-steam in said blastpi e to produce the usual draft or by using o y part ofthe exhaust to roduce a current of gas from the furnace to tige funnel, connecand desire ICO tions between the blast pipe and. the injecln witness whereof I have hereunto set Iny tors, a steam-blower, a live-steam pipe leadhund, this 11th day of July, 1905, in presence ing from the boiler to the injectors, and e disof two subscribing Witnesses.

tributer located in the live-steam pipe for ALEXANDRE HONOR MAZERAUD. controlling the supply of steam to the in- Witnesses:

jectors and steam-blower, substantially as LOUIS RiNERY,

described. HANsoN A. CoXE. 

